Apparatus for dialyzing liquids



Sept. 30, 1930. 0. M URBAIN 1,777,057

APPARATUS FOR DIALYZING LIQUIDS Filed J.u1y 13, 1928 Patented Sept. 30, 1930 'UNITED STATES OLIVER URBAIN, OF COLUMBUS, OHIO,

ASSIGNOR T0 THE OHIO SANITARY ENGI- NEERING CORPORATION, OF COLUMBUS, OHIO, .A CORPORATION OF OHIO APPARATUS FOR DIALYZING LIQUIUS application mea my 13,

This invention relates to an improved apparat/us for dialyzing liquids for the purpose of separating colloids from crystalloids contained in the liquid. y

I am aware that dialyzers have been used for separating soluble crystalloid substances from'collodial substances in a mixture based on the principle that crystalloids will di'use readily through a moist membrane such as a sheet of parchment paper Heating in water, while the colloids will not diffuse through the membrane.

rllhe known dialyzers do not, however, give accurate results particularly when the mixture dialyzed possesses characteristics whichvr c'ause its composition to change during the period required for the, dialyzing of the liquid, such for example, as piitrescible liquids of the character of domestic sewage and various industrial wastes, which putrefy rapidly in the presence of oxygen, even :it room temperature. A successful dialyzing operation requires considerable time, frequently several days. A putrescible liquid variesf so readily under the conditions employed in the known dialyzing operations that at the end of the operation it is in no sense comparable to the original material. The present invention contemplates the provision of an improved dialyzer and one more especially adapted for separating the colloids contained in a putrescible liquid from the crystalloids-Iin 'solution in such liquids whereby the true colloidal content of such a putrescible liquid may be denitely and accurately ascertained.

More specifically the present invention contemplates the provision of a dialyzer of such character that the dialyzing operation may be ed'ected at low temperature in the absence l ot oxygen and the dialyzing membrane kept moist by water, the dissolved oxygen of which has been removed, whereby putrefaction of, and bacterial growth in, the liquid l'being dialyzed is prevented;

The accompanying drawing illustrates the present preferred embodiment of my invention: It will beunderstood, however, that the titl broad principles oi my invention may be ef- 1928. Serial No'. 292,536.

ectively employed in other embodiments than that illustrated.

In the drawings, the reference character 1 designates the outer or water containing vessel of my dialyzer. 'Suitably floated in the water in the vessel l is a tray 2 for containing the liquid to be dialyzed. The tray 2 should be of suiicient area that the liquid therein need not be maintained at an excessive depth. I prefer to have the liquid in the tray at a depth of from substantially 1A to 1/2 inch, lthough this is merely illustrative. The tray 2 is so weighted that the surface of the liquid in the tray is slightly higher than the surface of the water in the vessel 1. This permits the operator to make the necessary correction in the volume of the liquid dialyzed after completion of the dialyzing operation by adding distilled water to equal the original volume. llt will be understood that the tray 2 maybe made from a parchment membrane or other suitable dialyzing membrane having its marginal edge held between the hooks 2a. i

rlhe vessel l is suitably supported within an outer container or box member 3. The arrangement is such that the box 3 is considerably larger than the vessel 1. The space a between the walls of the box and the vessel 1 is preferably filled with ice, as indicated in the drawings. This ice pack enables the operator to keep the contents'of the dialyzer tray 2 at a temperature suliciently low to prevent putrefaction under the vexisting conditions. 'I preferito maintain the temperature at from l to 2o C. .This will, however, vary, depending upon the character of the liquidbeing hasftwo valve controlled openings 7 and 8.,

the function of which is to permit the air in the vessel l to be exhausted therefrom at the commencement of the dialyzing operation and to be replaced by a suitable gas devoid of oxygen such, for example, as nitrogen. 'lhe air may be exhausted through the opening 7 by a. suitable pump, (not shown) and nitrogen admitted to replace the air through the openingl 8. When the air has been entirely replaced by a suitable gas, such as an atmosphere of nitrogen, the openings 7 and 8 are closed and hermetically sealed.

A thermometer 9 extends through a` hermetically sealed bushing 10 into the vessel 1 so that the temperature o the dialyzing Way ter may at all times be `observed, enabling an accurate control of the temperature conditions.

` A supply of distilled Water which has been heated to a boiling temperature to remove the dissolved oxygen content and cooled While out of contact with air is maintained in the reservoir 15. A suitable vessel 12 is provided which contains a quantity of potassium pyrogallate 13. An air inlet 11 communicates with the vessel12. As the water level in reservoir 15 recedes, due to the supply yof Water passing through .the dialyzer, the

nitrogen necessary to replace the liquid withdrawn from reservoir 15 is drawn in thorugh inlet 11 as air which bubbles through the potassium pyrogallate 13, the oxygen of the air being entirely absorbed thereby and permitting only pure nitrogen to enter the reservoir 15. Thus, the vessel 12 with its content of potassiumpyro allate serves as an oxygen trap, enabling t e operator to eiective y prevent any oxygen from entering the dialyzmg Water supply in 15. The rate of flow of the dialyzing Water through the dialyzer is approximately one pint per hour. rIhe water leaving'vessel 15 through line 16 enters the vessel 1 through a hermetically sealed bushing 18 similar to the bushing 10. The arrangement shown is such that the dialyzing water is supplied by gravity flow to the vessel 1. v

From the vessel 1 the dialyzing water with its crystalloid content passes through the outlet line 19, the discharge end of which is submer ed in a body of liquid 20 in the vessel 21, t e arran ement being such that a liquid seal is forme preventing any back How of air to the vessel 1. The spent liquid overows from theA vessel 21 through the outlet line 22.

The operation of my apparatus for dalyzing liquid will be apparent from the oref going description. Accordingly no detailed outline of the operation is deemed necessary. It will be noted that the dialyzing operation is effected in an atmosphere devoid of oxygen and by employing water, the dissolved Y oxy en content of whlch has been removed 1. A' dialyzer for putrescible liquids com! prising a shallow tray formed from a dialyzing membrane floated inthe Water in a receptacle, said tray being of relatively great area with respect to the surface of the water in said receptacle, means for supplying dialyzing Water to said receptacle, and overfiow means for permitting Water to pass from said rece tacle.

2. A dlalyzer for putrescible liquids comprising a shallow tray formed from a dialyzing membrane ioated in the Water in said Water receiving receptacle, means for supplying dialyzing Water to said receptacle, and overflow means for permitting Water to pass from' said receptacle.

3. A dialyzer for putrescible liquids comprising a Water recelving receptacle having a hermetically sealed closure, a shallow tray formed from a dial zing membrane fioated in the Water in sai Water receiving receptacle, means for supplying dialyzing water to said receptacle, a trap lnterposed in said water supply means for containing a chemical capable of removing the dissolved oxygen from the Water, and overiow means for permitting Water to pass from said receptacle. Y

OLIVER M. URBAIN. 

